Geek's Number Talk: As interest rates rise, the market falls.

With the Fed about to increase interest rates another three-quarters of a point, Wall Street is reacting, and not in a good way. The Dow Jones lost 876 points Monday — or nearly 3 percent — Nasdaq fell 4.7%, and the S&P 500 lost nearly 4%. Overall, the market is down 20% since January. Want to get more numbers? Have a listen to the PBS News Hour.